I have a 4.10 and the best gas mileage I can gett according to the speedo and the Odometer, is between 17-19 Miles (highway), with a pretty much stock Ls1, 4.10 and 315-35-17's in the back. maybe the 35 tire size? Will a 40 size improve at all? I was considering putting in the 3.73 at first but the 4.10 seemed niced for power, only problem is I put 2,500 miles a month on my Camaro because of my new job. 45 Miles each way. Anyone think by going to 3.73 I will still sustain significant gain over the stock gears.

 

i doubt it , i get about 18 in my car with the stock rear, it's all about how you drive that gets you the milage, if you shift at like 1,500rpm you will have execllent gas mialage, if you shift at 4,500 you will have poor gas milage.

 

It don't think it would be realyl meaningful to compare mpg with different people, beacuse there are too many variables involved...There's people that only get that on 3.42's.. then there's people that get like 27..

but I'd guess you'd probably gain at most 1 mpg for switching over to 3.73's, and maybe another mpg or two for going down to 3.42's.. thats probably best case scenario.

its all about lower revs, small throttle inputs, slower accel, and keeping a constant speed as much as possible.

 

If it makes you feel better I only get 11-12 MPG.